1. Field of the Invention
The present invention relates to an image processing system and an image processing method for digitally generating and controlling image data of an image to be formed on a sheet with an image forming apparatus.
2. Description of the Related Art
Recently, digital printing technologies have been increasing the utility value thereof in on-demand printing markets and document printing markets requiring a small number of documents.
Regarding full-color printing using an electrophotographic technology, not only full-color electrophotographic printing using toner of four colors (cyan, magenta, yellow, and black (CMYK)) but also multicolor printing using special toners are receiving attention.
One of these special toners is a transparent toner, which is a transparent recording material that does not have pigment, but does have a characteristic of adding a colorless transparent image.
By superimposing this transparent toner on an image, glossiness of the image can be controlled (see Japanese Patent Laid-Open No. 10-055085).
In addition, since a colorless transparent image can be added with a transparent toner, additional information can be added to an image while suppressing degradation of the image quality.
In this case, there is a usage example of a transparent toner that an image is formed with a transparent toner on a sheet having been subjected to electrophotographic printing to print information certifying that the printed result is the original.
The information printed with a transparent toner, which is usually invisible, becomes visible by irradiating the information with ultraviolet light, and it is possible to certify that the printed material is not duplicated by forgery or copying (see Japanese Patent Laid-Open No. 2003-118276).
Additionally, Japanese Patent Laid-Open No. 2007-127790 discloses an add-on function for adding an identification number of an apparatus that has printed a printed material to an image. By executing this add-on function using a transparent toner instead of a yellow toner, information can be added to an image while preventing image degradation.
Since a transparent image portion formed using a transparent toner has glossiness different from that of a sheet, this transparent image portion can be discriminated with human eyes.
However, since a printed material containing such a transparent image portion does not have colors that can be discriminated with a scanning ability of a scanner, the scanner may not be able to scan the transparent image portion.
The original is guaranteed by using such a characteristic.
For example, when a character string or a mark that specifies a distribution destination is added to a document, the original of this document can be discriminated with human eyes based on a difference in glossiness of the transparent-toner-applied portion. Thus, the document can be recognized as the original.
However, when this document is copied with a copier, the transparent-toner-applied portion vanishes in the copy. Thus, the copy can be discriminated from the original.
In this original guarantee method using a transparent toner, printing can be advantageously performed without degrading the color, tone, and resolution of an original image although uniform glossiness of the original image is lost.
A transparent toner may be used on the whole surface of a sheet to produce uniform glossiness in addition to a case where the transparent toner is used partially as in the above-described guarantee of the original and in a case of expressing the glossiness.
When a transparent toner is used to express the uniform glossiness on the whole surface of a sheet, the transparent toner is used at an imageless portion in addition to an image-containing portion. Thus, the transparent toner is used up more rapidly than the other toners.
If the transparent toner is used up at the time of performing transparent printing using the transparent toner for the original guarantee, the original guarantee printing has to be paused until the transparent toner is replenished.
In addition, if a printer capable of performing transparent printing cannot carry out the transparent printing for some reason and data is transferred to, for example, a printer not having a function for performing transparent printing with a transparent toner, the original guarantee cannot be realized.
Accordingly, the printing has to be paused until a printer having a transparent printing function is ready for printing.
A document including a transparent printing setting as well as an image will now be discussed.
A creator of this document configures the transparent printing setting to form an image while superimposing a transparent toner on the image when this document is printed.
However, if this document is printed by a printer not having the transparent printing function, an image that should be printed with a transparent toner is not printed and useless printing not intended by a user having created this document is undesirably performed.